Imam al-Jawad (a) was born in last years of Imam al-Rida's (a) life. They have said that before his birth, Imam al-Rida (a) had no children and some enemies spread this rumor that Imam al-Rida (a) is not going to leave any lineage after himself and the chain of imamate will be broken. According to narrative sources, when Imam al-Jawad (a) was born and they brought him to his father; Imam al-Rida (a) said, "This is a child, more blessed than him is not born for our followers."

After Imam al-Rida (a) was martyred, some Shi'a called his brother, 'Abd Allah b. Musa, as the next Imam. Some others followed Waqifids, but most Shi'a accepted the imamate of Imam al-Jawad (a) even though he (a) was an 8-year-old child.

Scientific debates of Imam al-Jawad (a) in his childhood age with religious scholars of different Islamic sects in theological issues such as the position of caliphs and in jurisprudential issues such as hajj rituals are among well-known debates of Imams (a).

Imamate of Imam al-Jawad (a) was contemporary with two Abbasid caliphs: the first was al-Ma'mun (193/809 to 218/833) and Imam (a) spent 23 years of his life at the time of his caliphate. The second was al-Mu'tasim al-Abbasi (218/833 to 227/842) two years of his caliphate were contemporary with imamate of Imam al-Jawad (a).